Performance comissioned by Artmov International Festival of Mobile Medias

At the performance Burro Sem Rabo (Tailless Donkey) the city is transformed into an interface to create a sound piece played remotely through mobile wireless data transmission – a GSM mobile device.

It is a walk by the city knowing only the start and ending points. Along the route, a number of sound interventions are made in the city mixing oscilating tones, noises and sampled beats with the daily sound fabric of the city. All these inputs will be recorded during the drift and then in the end will be processed and combined in a final intervention of electronic music.
Burro sem rabo is the name of a cart used by city dwellers and recyclers who live off the leftovers of society. Here the cart is fitted with various devices: digital recorder, sampler, synthesizers, lap-top, mobile internet connection, 30 meters of AC cord, subwoofers, drivers, tweeters and “sample honks” used by Brazil’s informal service vans to call for clients.

The cart presented will be equipped with a GPS device. Continuing their research of immersion and urban intervention, Hapax prepares a meeting with the metropolitan public space aimed to intervene on the worn routine of home/work/leisure. With a stranger’s gaze, the group will enter the heart of the city and cross ghettos, alleys, streets, faces, corners, traces and avenues. Penetrate the nervous center of the city and expand the vital powers of a planed city reinvented as music.

All the coordinates of the drift will be transmitted through a GSM cellphone from the GPS device to an internet server, where they will be stored and retransmitted in real time to a computer mounted in a galerie, running two softwares: one musical and another converting GPS data into MIDI (Musical Instrument Digital Interface) signals. The signals originating from the GPS coordinates will then modulate synthesizers and samplers. Computer, PA system and video projector will conform an audio-visual environment, the very ending point of the musical drift. In this place, the festival’s audience and the general public will be able to follow the path of the artists: visually, with a line that indicates the displacement of the cart; and also on the sound dynamics generated by this same displacement. The route will gradually appear onscreen in real-time while a set of sounds chosen by the group will be automatically manipulated by the GPS coordinates of the cart.

What is being played in this technology invented by Grupo Hapax? Every movement can be decomposed in several parameters as distance, curve angles, speed and so on. Likewise, sound can be decomposed: volume, tone, rhythm. Indexing the GPS coordinates we can make them correspond, transforming movement parameters in sound parameters. Hapax warns: from now on, bus drivers, walkers or the police car can be playing music.